Forcing axioms for $λ$-complete $μ^+$-C.C

Saharon Shelah

Published 2013-10-15, updated 2020-07-29Version 2

We note that some form of the condition "$p_1, p_2$ have a $\leq_{\mathbb{Q}}$-lub in $\mathbb{Q}$" is necessary in some forcing axiom for $\lambda$-complete $\mu^+$-c.c. forcing notions. We also show some versions are really stronger than others.